The present invention relates to portable electronic devices such as portable telephones, and more particularly to a construction of two circuit boards being secured in the interior of a casing.
With reference to FIG. 4, conventional portable telephones comprise a casing 1 formed by a front case 11 and a rear case 12. A display 13 and a plurality of manual keys 14 including a seesaw key 15 are provided on the front case 11. The casing 1 has a first circuit board 3 disposed in its interior as shown in FIG. 5. Arranged on the first circuit board 3 are a key input device 4 to be depressed by the manual key 14, the display 13, a high-frequency circuit module 50, and a vibrator 2 comprising a motor 22 and an eccentric weight 21 attached to the output shaft of the motor for notifying the user of incoming calls, etc.
The high-frequency circuit module 50 comprises, as illustrated in FIG. 6, a chassis 51 having a surface of resin body processed with electroless plating, a second circuit board 32 fixed to the chassis 51 with screws fastened, and a shield case 55 attached to the second circuit board 32. A pair of arms 52, 52 extending on the opposite ends of the chassis 51 are engaged with the opposite ends of the first circuit board 3, having the high-frequency circuit module 50 attached to the first circuit board 3. A male connector 61 attached to the rear surface of the first circuit board 3 and a female connector 62 attached to the surface of the second circuit board 32 fit to each other, having the both boards 3, 32 electrically connected to each other.
With the conventional portable telephones, when external impulsive force is exerted on the casing 1, the first circuit board 3 and the high-frequency circuit module 50 must be prevented from moving in the casing 1. Such a construction, thus, is adopted that the opposite ends 31, 31 of the first circuit board 3 are engaged with ribs 10, 10 projecting inwardly of the casing 1, to prevent the first circuit board 3 from moving by the support of the interior of the casing 1.
However, with the above construction, a pair of arms 52, 52 extending on the chassis 51 are merely in engagement with opposite ends of the first circuit board 3, only to have the high-frequency circuit module 50 attached to the first circuit board 3. The high-frequency circuit module 50, thus, is not connected to the first circuit board 3 with the sufficient connecting strength to cause a relative shift between the first circuit board 3 and the second circuit board 32 in the event that external impulsive force is exerted. As a result, the problems are encountered including a male connector 61 and a female connector 62 are removed from the board or the portion wherein the male connector 61 is engaged with the female connector 62 is impaired.
An object of the present invention is to provide portable electronic devices comprising a first circuit board 3 and a second circuit board 32 disposed in an interior of a casing 1, a male connector 61 attached to one circuit board and a female connector 62 attached to the other board engaged with each other, and to prevent the male connector 61 and the female connector 62 from being impaired resulting from the exertion of the impulsive force.
The present invention provides a portable electronic device comprising the first circuit board 3 disposed in the interior of the casing 1, a circuit module 5 attached to the first circuit board 3. The circuit module 5 includes a chassis 51 engaged with the first circuit board 3 and the second circuit board 32 secured to the chassis 51. The male connector 61 attached to one circuit board and the female connector 62 attached to the other circuit board are engaged with each other to have the both circuit boards 3, 32 electrically connected.
On respective ends of chassis 51, a pair of arms 52, 52 holds and grips the respective end faces of the first circuit board 3. The pair of arms 52, 52 extends toward the first circuit board 3. Each upper end of the arms 52, 52 is held between an end face of the first circuit board 3 and an inner face of the casing 1.
With the portable electronic device, the invention not only adopts the construction that the chassis 51 of the circuit module 5 is engaged with the first circuit board 3, but also adopts the construction that the upper end of the pair of arms 52, 52 extending from the chassis 51 is held between an end face of the first circuit board 3 and an inner face of the casing 1. Therefore, the chassis 51 is connected to the first circuit board 3 with given more improved strength than in the prior art.
Accordingly, even if external impulsive force acts on the casing 1, there is no likelihood that relative shift occurs between the first circuit board 3 and the second circuit board 32. This prevents the male connector 61 and the female connector 62 from being impaired.
Stated specifically, the arm 52 of the chassis 51 contacts with the end face of the first circuit board 3 and with the inner face of the casing 1 on a plane including the first circuit board 3. With the specific construction, when external impulsive force acts on the casing, the force with which the first circuit board 3 presses the arm 52 and the force with which the inner face of the casing 1 receives the arm 52 are opposed on a same line, so that the impulsive force acts as force to compress the arm 52, causing no moment. As a result, the sufficient endurance is achieved in the event of the impulsive force exerted.
Further stated specifically, upper ends of a pair of arms 52, 52 extending from the chassis 51 are engaged with the respective ends of the first circuit board 3, to have the circuit module 5 attached to the first circuit board 3. According to the specific construction, the pair of arms 52, 52 extending from the chassis 51 also works as a construction to have the chassis 51 engaged with the first circuit board 3, giving the device simplified construction.
As stated above, the present invention provides the portable electronic device comprising the circuit module 5 which is connected to the first circuit board 3 with enough strength. Consequently, even if external impulsive force is exerted, the relative shift between the first circuit board 3 and the second circuit board 32 is avoided, to prevent the male connector 61 and the female connector 62 from being impaired.